Users of communication networks commonly engage in multimedia communication sessions, such as streaming video, voice over internet protocol (VoIP) calls, and other multimedia applications. The session initiation protocol (SIP) is typically used for controlling communication sessions consisting of one or more multimedia streams. Generally, SIP defines the messages that are sent between peers which control establishing, modifying and terminating multimedia sessions. In some examples, an IP multimedia subsystem (IMS) may be employed that supports streaming media sessions and other types of communication services. IMS typically utilizes SIP to facilitate communication session setup and tear-down to enable delivery of real-time IP multimedia services to communication devices operated by users requesting these services.
In a SIP peering environment, SIP links or pools of links may be established between operators of different domains based on operator-defined routing logic. These SIP links are typically identified by domain names and provisioned as service (SRV) records in a domain name system (DNS) server with the appropriate weights and priorities for optimal traffic distribution. Once a SIP link is established between peers, an operator can utilize the link to establish communication sessions and send traffic that requires termination in a different domain controlled by the other operator, without having to transfer the data indirectly over the internet or other, less reliable communication networks.